The Yaxell Manual Knife Sharpener with Waterstone is designed for all knives to sharpen the blade to a 12 degree angle. Simply remove the cap, fill the compartment with water and close the cap. Take a knife and insert the blade into one of the grooves at a 90 degree angle. With moderate pressure, pull the knife towards you about 10 times. Repeat the same process using the other groove. After sharpening, hand wash the knife in hot water and dry with a soft cloth, blade side up.